Three weeks after cardiac transplantation, what physiological response should a physical therapist anticipate?

Following cardiac transplantation, a significant physiological adaptation begins to occur as the body responds to the new heart and the interruption of neural regulation. One of the key responses anticipated in this scenario is an increase in resting heart rate.

This increase can be attributed to the loss of autonomic control over heart rate due to the severing of autonomic nerve pathways during the transplantation procedure. The transplanted heart relies on circulating catecholamines (hormones like adrenaline) rather than the direct neural input that would typically modulate heart rate based on physiological demands. As a result, individuals who have undergone cardiac transplantation may experience a higher resting heart rate compared to pre-transplant rates.

In addition, the ability to increase heart rate in response to exercise can be impaired initially after transplantation. The heart rate response to exercise may not be as significant as it is in individuals with an intact autonomic nervous system, leading to further distinctions in exercise responses when compared to non-transplanted individuals. Understanding these changes helps physical therapists tailor rehabilitation programs that are conducive to safely enhancing cardiac output and improving physical function post-transplant.